Insecticide and the like



Patented July 9, 1935 UNITED STATES PATENT OFFICE INSECTICIDE AND THE LIKE Frank Floyd Lindstaedt,

Oakland, Calif., assignor to Hercules Glue Company, San Francisco, Calif., a corporation of California No Drawing.

Original application May 17, 1930,

26 Claims.

My invention relates to toxic substances and particularly to such substances as are intended for use as insecticides, ovacides, iarvicides, and for the destruction of pests. Although intended primarily for external application, as for example in the form of a spray upon substances exposed to the air, as vegetables, it may nevertheless be employed in certain instances internally, as for example, when employed in the treatment of worms, or like parasites in the digestive tract.

The advantages of nicotine and like alkaloidal derivatives of tobacco or synthetic volatile alkaloids for such uses as above explained have long been recognized. These alkaloids, of which nicotineis the major derivative, are, unfortunately, quite volatile. Nicotine sulphate, which is the form commonly employed for the application of nicotine in the form of a spray, loses its effectiveness in a few hours when exposed to the atmosphere, and while it is eifective by reason of its volatility during this period, it has no further efiect thereafter.

One of the chief objects of my invention, therefore, is to produce a new chemical compound of a volatile alkaloid or alkaloids, which will retard the liberation of the volatiles, such as nicotine, so that they remain effective for considerable periods, increasing the efiectiveness of nicotine whenever it may be developed, as a spray, for example, and making possible its internal administration.

Another object of my invention is to produce a nicotine compound for such purposes as are indicated above, and analogous uses, from which the nicotine may be slowly liberated, to act by contact and ingestion to kill pests, previous nicotine compounds having acted largely by suffocation.

Another object of the invention is to provide a nicotine compound which can be successfully applied to various uses, for instance as a spray, but from which the nicotine cannot be dissolved. The utility of this is apparent for when applied to a surface, rain will not wash out the nicotine from the spray.

The invention possesses numerous other objects, the features of advantage, some of which, with the foregoing, will be set forth in the following description of my invention. It,is to be understood that I do not limit myself to this disclosure of species of my invention, as I may adopt variant embodiments thereof within the scope of the claims.

In my previous application Serial No. 453,416

filed May 17, 1930, a refile of my abandoned application of May 28, 1928, Serial No. 281,372, and of which this case is a. division, I disclosed compounds of a volatile alkaloid as nicotine alkaloid and abietic and alginic acids. These compounds were formed by reacting a molecular weight of the alkaloid with a molecular weight of the acid.

The reaction of colophony and nicotine has been proposed by Swiss Patent 114,438. Colophony, as is well known, is about 92% abietic anhyd'rid, (C2oH29O2)2O. Now the material alleged to have been produced in the Swiss patent, stated to be of a honey-like consistency and easily dissolved in water, is made by reacting 1.36 parts of colophony with a part of nicotine.

I have discovered that when the proportion of colophony to nicotine, for example, is increased, the consistency and solubility are different from that in the Swiss patent and the nicotine alkaloid is combined so that it does not dissolve in water. On the basis of molecular weights, assuming colophony to be pure abietic anhydrid, the ratio of weights of colophony to nicotine alkaloid is about four to one. As this ratio is approached, the reaction mass becomes a solid, losing any plasticity at ordinary temperatures and being capable of being ground up into finely divided form. The reaction product of the rosin (abietic acid) and nicotine is, I believe, a salt. Nicotine is a di-tertiary base so that, when heated with an acid it probably reacts therewith to form the salt, the acid being added onto the base, probably onto the C5H10N group since it is known to be more basic than the N in the pyridine ring. Alkaloids are defined as nitrogeneous basic materials usually containing nitrogen in a heterocyclic ring; irrespective of definition they are basic materials to which rosin can be added.

In practice I have employed quantities close to the molecular proportions, from four to seven times the weight of rosin being used. The rosin was melted in a vessel and heated to its boiling point when the alkaloid was added. The mixture was kept at a boiling temperature for a minute or two when it was allowed to cool and solidify after which it was comminuted. The nicotine alkaloid is combined in sucha form that even after fortyeight hours soaking in water no trace 'of the alkaloid can be detected in the water although the alkaloid per se is very soluble in water.

The invention is applicable to other volatile alkaloids particularly coniine. Nicotine and coniine are both classified as alkaloids derived .from pyridine. Volatile alkaloids is a clearly recognized class of alkaloid-see Allens, Commercial Organic Analysis, (Copyright 1912) vol. 6, page 207. In addition, materials can be used in place of rosin or colophony which are closely akin thereto and which are recognized practically as equivalents insofar as this invention is concerned in that they contain a considerable percentage of abietic acid or react with nicotine to form compounds of much the same properties and qualities as nicotine abietate.

The final substance, prepared in the manner stated or in a manner not deviating from the spirit of the invention, may be used as a spray upon vegetation, or in other places where it is desired to destroy insects, grubs, parasites or the eggs thereof. It may be supplied for such purposes in granulated form, ready to mix with large quantities of a spray medium. Thus applied the nicotine resinate slowly decomposes, the nicotine being freed, and apparently the rosin remaining. The nicotine is slowly given off and remains in association with the thing-which has been sprayed, over long periods, whereas nicotine dis appears from known nicotine compounds, as nicotine sulphate, in a few hours, more or less, depending upon temperature and humidity conditions. Under the same conditions nicotine can be detected in toxic quantities on the article sprayed with the nicotine resinate for a period of eight to fourteen days or longer, even though the article has been wet.

This is a decided advantage in many ways. For the orchardist, for example, who sprays his trees for insects or pests, the first application will perhaps kill or drive away the pests, but if the nicotine disappears after a few hours, a change in the wind, or improvement in reproducing conditions may cause reinfestation, and the spraying must be repeated.

Where the efiect persists for long periods, as for a week or longer, it is not necessary to watch over the orchard so closely. Furthermore, should the pests deposit their eggs before being driven off or killed by the first spray, the eggs themselves will be destroyed by osmosis; that is to say, all life within them will be destroyed by the intimate association with, and permeation by the nicotine; or the grubs on hatching, will eat the nicotine and be killed. Not only will this reduce the cost of spraying, but it will reduce the labor attendant upon keeping close watch over the orchard, and frequent repetition of the spraying process.

I claim:

1. Water insoluble nicotine abietate.

2. A water insoluble reaction product of nicotine alkaloid and abietic acid.

3. A water insoluble reaction product of a volatile alkaloid and abietic acid.

4. The product resulting from reacting approximately molecular weights of abietic acid and nicotine.

5. The product resulting from reacting approximately molecular weights of abietic acid and a volatile alkaloid.

6. Abietic acid having combined therewith nicotine alkaloid sufiicient to form a substantially water insoluble product.

7. Nicotine combined with an excess of rosin.

8. A volatile alkaloid combined with an excess of rosin.

9. Water insoluble nicotine rosinate.

10. The substantially water insoluble solid resulting from the reaction of nicotine and rosin.

11. The substantially water insoluble solid resulting from the reaction of a volatile alkaloid and rosin.

12. An aqueous spray mixture having water insoluble nicotine abietate suspended therein.

13. An aqueous spray mixture having water insoluble reaction product of nicotine and rosin suspended therein.

14. An aqueous spray mixture having the product formed upon reaction of an excess of rosin with a volatile alkaloid suspended therein.

15. An aqueous spray mixture having the product formed upon reaction of an excess of rosin with a volatile base suspended therein.

16. The reaction product of rosin and coniine.

17. Water insoluble coniine abietate.

18. Coniine abietate.

19. The water insoluble reaction product of rosin and an alkaloid derived from pyridine.

20. The water insoluble product of addition of nicotine and rosin.

21. The water insoluble addition product of rosin and a pyridine base.

22. The addition product abietic acid and a pyridine molecular proportions.

23. The addition product produced by reacting abietic acid and an alkaloid derived from pyridine in substantially molecular proportions.

24. The addition product produced by reacting abietic acid and coniine in substantially molecular proportions.

25. Anhydrous nicotine abietate insoluble in water.

26. The water insoluble reaction product of nicotine and abietic anhydrid.

FRANK FLOYD LINDSTAEDT.

produced by reacting base in substantially 

